1 page.title=Android 2.3.4 APIs 2 excludeFromSuggestions=true 3 sdk.platform.version=2.3.4 4 sdk.platform.apiLevel=10 5 6 7 @jd:body 8 9 <div id="qv-wrapper"> 10 <div id="qv"> 11 12 <h2>In this document</h2> 13 <ol> 14 <li><a href="#api">API Overview</a></li> 15 <li><a href="#openaccessory">Open Accessory Library</a></li> 16 <li><a href="#api-level">API Level</a></li> 17 </ol> 18 19 <h2>Reference</h2> 20 <ol> 21 <li><a 22 href="{@docRoot}sdk/api_diff/{@sdkPlatformApiLevel}/changes.html">API 23 Differences Report »</a> </li> 24 </ol> 25 26 </div> 27 </div> 28 29 <p> 30 <em>API Level:</em> <strong>{@sdkPlatformApiLevel}</strong></p> 31 32 <p>Android 2.3.4 ({@link android.os.Build.VERSION_CODES#GINGERBREAD_MR1}) 33 is a maintenance release that adds several bug fixes and patches 34 to the Android 2.3 platform, without any API changes from Android 2.3.3. Additionally, 35 Android 2.3.4 brings support for the Open Accessory API to mobile devices, 36 through the optional <a href="#usb">Open Accessory Library</a>. </p> 37 38 <p>For developers, the Android {@sdkPlatformVersion} platform is available as a 39 downloadable component for the Android SDK. The downloadable platform includes 40 an Android library and system image, as well as a set of emulator skins and 41 more. To get started developing or testing against Android {@sdkPlatformVersion}, 42 use the Android SDK Manager to download the platform into your SDK.</p> 43 44 45 46 <h2 id="api">API Overview</h2> 47 48 <p>Android 2.3.4 provides the same framework API to applications as Android 2.3.3 49 (API level 10). For a summary of the API, see the 50 <a href="{@docRoot}about/versions/android-2.3.3.html">Android 2.3.3 version notes</a>.</p> 51 52 53 <h2 id="openaccessory">Open Accessory Library</h2> 54 55 <p><em>Open Accessory</em> is a new capability for integrating 56 connected peripherals with applications running on the platform. The capability 57 is based on a USB (Universal Serial Bus) stack built into the platform and an 58 API exposed to applications. Peripherals that attach to Android-powered devices 59 as accessories connect as USB hosts. </p> 60 61 <p>Open Accessory is introduced in <a 62 href="{@docRoot}about/versions/android-3.1.html#usb">Android 3.1</a> (API level 12), but is 63 made available to devices running Android 2.3.4 by means of an optional external 64 library, the Open Accessory Library. The library exposes a framework API that 65 lets applications discover, communicate with, and manage a variety of device 66 types connected over USB. It also provides the implementation of the API against 67 parts of the Android platform that are not directly exposed to applications in 68 Android 2.3.4.</p> 69 70 <p>The Open Accessory Library is optional on any given device. Device 71 manufacturers may choose whether to include the Open Accessory Library in their 72 products or exclude it. The library is forward-compatible with Android 3.1, so 73 applications developed against Android 2.3.4 will run properly on devices 74 running Android 3.1, if those devices support USB accessories. </p> 75 76 <p>The API provided by the Open Accessory Library is based on the Open Accessory 77 API provided in Android 3.1. In most areas, you can use the same techniques and 78 APIs. However, developing for the Open Accessory Library on Android 2.3.4 differs 79 from the standard USB API in these ways: 80 81 <ul> 82 <li>Obtaining a {@link android.hardware.usb.UsbManager} object — To obtain 83 a {@link android.hardware.usb.UsbManager} object when using the add-on library, 84 use the helper method <code>getInstance()</code> rather than {@link 85 android.content.Context#getSystemService(java.lang.String) getSystemService()} 86 For example: 87 88 <pre>UsbManager manager = UsbManager.getInstance(this);</pre></li> 89 90 <li>Obtaining a {@link android.hardware.usb.UsbAccessory} from a filtered intent 91 — When you filter for a connected device or accessory with an intent 92 filter, the {@link android.hardware.usb.UsbAccessory} object is contained 93 inside the intent that is passed to your application. If you are using the 94 add-on library, you can get the {@link android.hardware.usb.UsbAccessory} object 95 in the following manner: 96 97 <pre>UsbAccessory accessory = UsbManager.getAccessory(intent)</pre></li> 98 99 <li>No USB host support — Android 2.3.4 and the Open Accessory Library do 100 not support USB host mode (for example, through {@link 101 android.hardware.usb.UsbDevice}), although USB host mode is supported in Android 102 3.1. An Android-powered device running Android 2.3.4 can not function as a USB 103 host. The library enables the Android-powered device to function as 104 a peripheral only, with the connected accessory functioning as USB host 105 (through {@link android.hardware.usb.UsbAccessory}).</li> 106 </ul> 107 108 <p>To develop apps using the Open Accessory Library, you need:</p> 109 110 <ul> 111 <li>The latest version of the Android SDK tools</li> 112 <li>The latest version of the Google APIs add-on, which includes the library 113 itself (for linking)</li> 114 <li>An actual hardware device running Android 2.3.4 (or Android 3.1) with USB 115 accessories support, for runtime testing against connected devices</li> 116 </ul> 117 118 <p>For a full discussion of how to develop applications that interact with USB 119 accessories, please see the related <a 120 href="{@docRoot}guide/topics/connectivity/usb/index.html">developer documentation</a>.</p> 121 122 <p>Additionally, developers can request filtering on Google Play, such that 123 their applications are not available to users whose devices do not provide the 124 appropriate accessory support. To request filtering, add the element below 125 to the application manifest:</p> 126 127 <pre><uses-feature 128 android:name="android.hardware.usb.accessory" 129 android:required="true"></pre> 130 131 132 <h2 id="api-level">API Level</h2> 133 134 <p>The Android 2.3.4 platform does <em>not</em> increment the API level — 135 it uses the same API level as Android 2.3.3, API level 10. 136 137 <p>To use APIs introduced in API level 10 in your application, 138 you need compile the application against the Android library that is provided in 139 the latest version of the Google APIs Add-On, which also includes the Open 140 Accessory Library.</p> 141 142 <p>Depending on your needs, you might 143 also need to add an <code>android:minSdkVersion="{@sdkPlatformApiLevel}"</code> 144 attribute to the <code><uses-sdk></code> element in the application's 145 manifest. If your application is designed to run only on Android 2.3.3 and higher, 146 declaring the attribute prevents the application from being installed on earlier 147 versions of the platform.</p> 148 149 <p>For more information, read <a href="{@docRoot}guide/topics/manifest/uses-sdk-element.html#ApiLevels">What is API 150 Level?</a></p> 151